Formulation Of Solid Self-Emulsifying Drug Delivery System Using Mixedtocotrienols As The Model Drug

Loading...
Thumbnail Image
Date
2020-04
Authors
Lee, You Zhuan
Journal Title
Journal ISSN
Volume Title
Publisher
Universiti Sains Malaysia
Abstract
The present study was conducted to develop and evaluate the formulation of a solid self-emulsifying system for enhancing the oral bioavailability of a poorly water-soluble liquid active compound, namely tocotrienols. A suitable solid carrier with high liquid holding capacity was selected. Various properties of several solid self-emulsifying formulations including emulsification efficiency, emulsion droplet size, desorption and powder flow properties were investigated. A solid selfemulsifying formulation with the desired properties was successfully developed, using magnesium aluminosilicate (Neusilin US2) as the solid carrier, containing 65 to 70% TRF and 30 to 35% surfactants (poloxamer and Labrasol) with sodium lauryl sulphate as wetting agent. The formulation showed good self-emulsification efficiency with stable emulsion formed, demonstrated excellent powder flowability, complete desorption of tocotrienols from carrier, and small emulsion droplet size of 210 to 303 nm. Subsequent in vivo studies using Sprague-Dawley rats showed that the formulation with a combination of surfactants (poloxamer and Labrasol) had a faster rate of absorption compared to using only single surfactant (either poloxamer or Labrasol). In a following in vivo study, the solid self-emulsifying preparation with combined surfactants (D4) showed enhanced oral bioavailability (3.4 to 3.8 times higher) compared to the non self-emulsifying oily liquid preparation when administered at fasted state in rats. The formulation which was in a dry powder form was further developed into a hard gelatin capsule dosage form, containing 100 mg tocotrienols in each capsule. Granules were prepared by wet granulation with the addition of PVP K30 as binder at 5.2 %w/w per capsule. The granules showed high bulk density, excellent flow properties and emulsification efficiency with Carr’s compressibility index, Hausner ratio and angle of repose in the category of ‘good’ to ‘excellent’. Release of the tocotrienols from the capsule was complete and the emulsion formed had droplet size in the submicron range. The bioavailability of tocotrienols from the capsules was evaluated in comparison to a commercial liquid self-emulsifying product, Tocovid® Suprabio® in 8 human volunteers. The results showed that the oral bioavailability of the capsules was comparable to that of Tocovid® Suprabio®, which has been demonstrated to enhance the bioavailability of tocotrienols by 3-fold compared to a non self-emulsifying oily preparation. In conclusion, the solid self-emulsifying formulation of tocotrienols in a hard gelatin dosage form was able to enhance the oral bioavailability of tocotrienols and was comparable to a commercial liquid self-emulsifying product which has been shown to enhance the oral bioavailability of the tocotrienols.
Description
Keywords
Pharmacy , Materia medica
Citation